• Year
  • 1951–1953
  • Category
  • Broadcast Receiver - or past WW2 Tuner
  • Radiomuseum.org ID
  • 29832

Click on the schematic thumbnail to request the schematic as a free document.

 Technical Specifications

  • Number of Tubes
  • 5
  • Main principle
  • Superheterodyne (common); ZF/IF 452 kHz; 2 AF stage(s)
  • Tuned circuits
  • 6 AM circuit(s)
  • Wave bands
  • Broadcast, Long Wave and Short Wave.
  • Power type and voltage
  • Alternating Current supply (AC) / 110; 125; 145; 200; 220; 245 Volt
  • Loudspeaker
  • Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 15 cm = 5.9 inch
  • Power out
  • 3 W (unknown quality)
  • Material
  • Bakelite case
  • from Radiomuseum.org
  • Model: BX310A - Philips; Eindhoven tubes
  • Shape
  • Tablemodel, low profile (big size).
  • Dimensions (WHD)
  • 380 x 250 x 200 mm / 15 x 9.8 x 7.9 inch
  • Notes
  • AM radio for external antenna:
    • LW: 152 - 285 kHz.
    • BC: 517 - 1622 kHz.
    • SW: 5,92 - 18,2 MHz.
    Loudspeaker: 9744X (5Ω).
    Dial lamp: 8045D (E10, 6,3V/320mA).
     
    In versions /53 and /90, there are some slight modifications in the parts but not in the general specifications. See the specific version schematics with this model page.
  • Net weight (2.2 lb = 1 kg)
  • 5.9 kg / 12 lb 15.9 oz (12.996 lb)
  • Literature/Schematics (1)
  • -- Original-techn. papers.
  • Literature/Schematics (2)
  • Dépliant Nouvelle Série Philips Radio 1953, Sept. 1952
  • Author
  • Model page created by Iven Müller. See "Data change" for further contributors.

 Collections | Museums | Literature

Collections

The model is part of the collections of the following members.

 Forum

Forum contributions about this model: Philips; Eindhoven: BX310A

Threads: 1 | Posts: 6

Hello Forum,
I am restoring a Philips radio type BX310A from 1951/-52. It is generally in quite good shape but has one painful fault; namely internal arcing (= random short circuit) between primary/secondary winding -S23- S24 in the audio output transformer. Trafo's Philips code is A3 152 18.0, and iron core (E+I) size is 40*37*16mm3. Output tube is EL 41 and O/P power 2-3W? The trafo is compact and impregnated with " black tar " so very difficult to open and rewind.
This fault had very interesting symptoms and not so easy to discover. When I smoothly increased AC input voltage by Variac, so around 150V became random "crackle" audible. At the same time one or more arcs happened on tube base socket from anode pin to ground (about 5mm) also a few arcs were visible inside of the tube, especially with higher AC input. These phenomena continued with random rate. Following the anode voltage with oscilloscope showed that the voltage dropped sharply during "crackles". I changed several components and also EL41 + socket at O/P stage without success.
So my final conclusion was a high resistant short circuit between the primary and secondary windings inside of the trafo. One leg of secondary is grounded. Attached drawing shows how I think this phenomenon happens. I also tested the trafo separately with DC voltage and the "crackle " repeated. Normal ohmmeter did not indicate leaking between windings.

Does the arcing happen due to "Spark Coil" effect just like in cars??

Can somebody to advice me are there any means to repair the trafo? Due to trafo construction, rewinding of it look very difficult because of the primary section seems to be top layer. What about availability of adequate replacement trafo (new or surplus)

Best regards
Ake Nyholm

Attachments

Ake Nyholm, 08.Mar.05

Weitere Posts (6) zu diesem Thema.